What game on steam did you play the most?

Also Gmod, with about 510+ hours.

Terraria with 125 hours

AoEO - 85 hours.

TF2 with over 400 hours, and I don't idle.

TF2: 1204 hours,
you're all lightweights.

TF2, over 900 hours.

I put a lot of time into Saints Row; Steam has a ridiculously high amount of play time (well, high for SR3 anyway) listed on my account cuz I left it open overnight once or twice, but if I remember correctly, the game itself says my save file has over 70 hours on it. And I still haven't even played all the DLC missions yet.

I'm glad Minecraft isn't a Steam game though because I'd rather not know how much time I've put into it.

Terraria: 40 hours. :3

If you combine my time playing TF2 on this laptop and my last one (my times reset when I got a new one), I believe the total is over 1600 hours.

Counter-Strike: Source with 1829 hours.

Football Manager 2013: 259.6 hours, but I'm usually multitasking while I play that because it doesn't require much user input.

As far as non-Steam, I've spent hundreds of hours with Hearts of Iron 2, Rome and Medieval: Total War, and SWAT 4.

TF2: 271 hours.

If we're counting non-Steam games, I spent thousands of hours in Hearts of Iron 2 and Stronghold Crusader back in the day.

Ys Origin 634 hours played. This is mostly because I completely fail at Nightmare time attack and have a very bad habit of clicking off the window when I need a break because I got so far in time attack and don't want to start over again!

Actually, a lot of my playtimes are inflated because I have the attention span of a gnat sometimes.

Binding of Isaac 215 Hours

TF2 - 716 Hours x) Although CS:S follows somewhat closely with 480... Oh dear, with all the other games I play added onto that... I really need to get out more xD

Team Fortress 2 lawl

Awesomenauts with like 245 hours.

Guild Wars with 311 hrs, after that is Killing Floor with 189 anf FV New Vegas with 113

dota 2 813 hrs

l4d with 3.2k hours almost

prolly cod series on my ps3 like 100+ hours

Non steam game. Meh i spent an entire year playing World of Warcraft abt 6-8 hours daily..
So much time wasted sigh

456 hours on CS 1.6

was my first steam game, and how i knew steam, i stoped playing about 4 years ago, i bought CS:GO for the memories, but i must admit that playing with little kids after being on indie heaven was unbearable, i hated them even when they where my own age, and i had a "no-steam" cracked versions of CS, i played no-steam for 3 years, so i think that should be arround 1000+ hours of CS.

nowdays i just like to play indies or singleplayer mostly

guild wars 2 450+ hours